The UK's Evolving Physical Landscape Flashcards
What is glacial abrasion?
A process of erosion involving the wearing away of the valley floor and sides. It also wears away shorelines in coastal zones.
What is glacial plucking?
A process of erosion involving individual rocks being plucked from the valley floor and sides as water freezes them to the glacier.
Outline the process of freeze thaw weathering and any outcomes of it:
Erosion caused due to water freezing in a crack, expanding, widening the rock and melting again.
This causes moraine and piles off scree.
What is the cause of meltwater and what does it do?
Ice melting in summer.
Lubricates the glacier, letting it move (basal/ rotational slip).
Why do glaciers move downhill in winter?
The glacier is frozen to the surface so its weight and gravity cause individual ice crystals to move. This is called internal deformation.
What are the 4 types of moraines?
-Lateral moraine
-Medial moraine
-Terminal moraine
-Ground moraine
How are arêtes and pyramidal peaks formed?
2 or more Corries form back to back
How are Corries formed?
1) Snow accumulates in a hollow hillside
2) Snow turns to ice, compressing the land and forming a small Corrie glacier
3) The glacier repeatedly scoops out rock (due to rotational slip and plucking)
4) A raised lip is formed as ice is thinner near the Corrie edges
5) After a glacial period, the ice melts to form a Corrie lake (tarn)
What is a hanging valley?
A valley which has been cut across by another deeper valley (usually resulting in a waterfall)
Name 7 glacial features of upland areas
-Arêtes
-Corries
-Tarn (Corrie lake)
-Hanging valley
-Plucking
-Misfit river
-Dry valley
What is carbon dating?
Using radioactive testing to determine the age of rocks, which contained living material
What are the three types of rock?
Sedimentary, Metamorphic, Igneous
What are layers of rock called?
Strata
What types of rock are found in high relief areas?
Igneous and Metamorphic as they are more resistant
What type of rock is found in low relief areas?
Sedimentary rock as they are less resistant
Where is sedimentary rock found?
East of England
Where is Metamorphic rock found?
West of England
Why are some parts of a valley worn away more easily than others?
They are made from a less resistant type of rock
How did tectonic processes affect the Pennines?
- Convection currents beneath the plate, uplifted rocks from below the sea, to form land
- Some rocks snapped and moved along faults over thousands of years in a series of earthquakes
- Each earthquake raised faults to different heights
How do V-shaped valleys form?
Rivers erode into the valley over time
How do U-shaped valleys form?
Glaciers erode further into the V-shaped valleys making wide troughs
Give an example of an igneous rock.
Granite
How is igneous rock formed?
Molten magma or lava cools slowly, forming crystals.
How is metamorphic rock formed?
Igneous or sandstone rocks get pushed under continental plates. The heat and pressure changes them into new rocks.
Give 2 examples of metamorphic rocks.
Schists
Slate
Give 3 examples of sedimentary rocks.
Chalk
Carboniferous limestone
Clay
What are the characteristics of igneous rock?
Heavy, dark, very resistant
What are the characteristics off metamorphic rock?
Resistant
What are the characteristics of sedimentary rock?
Soft and crumbly (Clay)
Permeable (Carboniferous limestone)
Porous and very resistant (Chalk)
What is slate made of?
Heated mud or shale
Where in the UK can you find sedimentary rock?
London- clay
Yorkshire dales- limestone
Where in the UK can you find igneous rock?
Dartmoor
Grampians
Where in the UK can you find metamorphic rocks?
Giants causeway
Stornaway
What are the 3 types of weathering?
Physical- weather
Chemical- acid rain
Biological- plants
Give an example of an upland UK landscape, the weathering types, the slope processes and the post-glacial processes:
The Lake District
Weathering: freeze thaw
Slope processes: rockfalls and landslides (large volumes of rain) forming steep, rocky crags
Post-glacial processes: misfit rivers and silt and mud deposition
Give an example of a UK lowland landscape, the weathering types, the slope processes and the post-glacial river and slope processes:
The Weald
Weathering: chemical and biological weathering
Slope processes: steep escarpments and flat vales (scarp and vale topography)
Post-glacial processes: dry valleys and flat land
What are the advantages and disadvantages of agriculture in the South Downs on the landscape?
+Hedgerows/field margins provide wildlife corridors
-Chemicals reduce soil fertility, erosion of chalk and shrub encroachment
What are the advantages and disadvantages of forestry in the South Downs on the landscape?
What are the advantages and disadvantages of settlement in the South Downs on the landscape?
What is a coastal zone?
A changing boundary between land and sea.
Give 2 examples of hard rock coasts.
Flamborough Head
Lulworth cove
Give 2 examples of soft rock costs.
Holderness coast
Happisburgh
What is a concordant coastline?
A coastline where the rocks are parallel to the wave front. Similar erosion rates throughout.
What is a discordant coastline?
A coastline were differential erosion may occur due to bands of hard and soft rock. This causes bays and headlands.
What is a joint?
A small, vertical crack found in many rocks
What is a fault?
A larger rack caused by past tectonic movements where rocks have formed
Describe how caves, arches, stacks and stumps are formed from hard rock cliffs.
-A large crack is opened up by hydraulic action
-The crack grows
-A cave forms and becomes larger
-The cave breaks through the headland forming a natural arch
-The arch collapses to form a stack
-The stack erodes into a stump
What causes waves?
Wind blowing across the sea causing friction.
What does wave size depend on?
Wind strength
Length of time wind is blowing for
Length of water
Describe a constructive wave.
Small, slow summer waves with long wavefronts and low amplitudes that break as spilling waves. They have a strong swash so lots of sand is deposited. They also have low backwash due to a gentle slope.
Describe a destructive wave.
Tall, quicker winter waves with a larger amplitude but shorter wavelength which breaks as a plunging wave. They have a strong backwash due to a steep beach which can form a rip current and offshore bars.
What is rotational slumping?
The rapid movement of a mass of earth or rock sliding along a concave surface. This occurs due to heavy periods of rain, human activity like new buildings and the nature of the material.
What is longshore drift?
Process by which sediment such as sand is transported along a beach. The direction is controlled by the direction of the dominant wind.
How do you find evidence of longshore drift?
Slanted beach
Groynes
Spits or sand dunes
What is a spit?
A neck of sand formed by deposition of sand on a river, halting its flow.
What is a beach?
Sediment on a coast forming a barrier between land and sea. This is usually due to a cove or bay.
What is a bar?
A line of sand covering/ blocking a bay from the sea due to longshore drift. This may form a lagoon.
What is a salt marsh?
A marsh behind a curved spit, protecting it from storms.
Which 4 human activities cause most risk to coasts?
Development
Agriculture
Industry
Coastal management
How does development impact coasts?
Tourism- pollution
Housing- slumping
Commercial activity/ businesses- slumping
Retirement homes- slumping
Why does development take place at the coast?
Businesses have easy access to trading ports.
Less money has to be spent on transport.
Fishing businesses have easy access to their docks.
How is agriculture impacted by coasts?
Sea level rise floods pastures with salt water
Increased coastal erosion leads to loss of farmland as it has low economic value
How does industry impact coasts?
Roads, railways and ports are built to link coasts to the rest of the world.
Oil refineries can cause leaks into the sea
Gas terminals and chemical plants produce many waste products
Wildlife is disturbed by ferry and shipping ports
Erosion due to sand and gravel removal disturbs wildlife
How does coastal management impact coasts?
Hard engineering protects coasts with artificial structures
Soft engineering protects coasts with natural process